US7773542B2 - Dual radio wireless mesh network access point - Google Patents

Abstract

A dual radio wireless mesh access point is described herein. According to one embodiment, a wireless mesh access point includes an uplink wireless interface, a downlink wireless interface, a local wireless interface, and a routing unit coupled to the uplink, downlink, and the local wireless interfaces. The routing unit is configured to route data packets to other wireless mesh access points (APs), including communicating with an uplink AP via the uplink wireless interface and communicating with a downlink AP via the downlink wireless interface. The uplink and downlink wireless interfaces utilize different communication channels having different communication frequencies. The routing unit communicates with one or more local clients via the local wireless interface. Other methods and apparatuses are also described.

Description

RELATED APPLICATION

This application claims the priority of U.S. Provisional Patent Application No. 60/939,314, filed May 21, 2007, which is incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to wireless networks. More particularly, this invention relates to a dual radio wireless mesh network access point.

BACKGROUND

Wireless mesh networks are gaining popularity because wireless infrastructures are typically easier and less expensive to deploy than wired networks. The wireless mesh networks typically include wired gateways that are wirelessly connected to wireless nodes, or wireless connected directly to client devices. Many wireless nodes can collectively provide a wireless mesh, in which client devices can associate with any of the wireless nodes.

Typically, the wireless nodes are implemented as wireless access points (APs). A typical wireless AP includes a local link interface to communicate with local client devices and a downlink and uplink interfaces to communicate with other APs. Conventional APs utilize the same communication frequency when communicating with other APs. As a result, there may be an interference between an uplink and a downlink communications and may have impact on the signal quality. In addition, communications between the wireless APs typically are in a form of plain text which may be vulnerable to be attacked.

SUMMARY OF THE DESCRIPTION

A dual radio wireless mesh access point is described herein. According to one embodiment, a wireless mesh access point includes an uplink wireless interface, a downlink wireless interface, a local wireless interface, and a routing unit coupled to the uplink, downlink, and the local wireless interfaces. The routing unit is configured to route data packets to other wireless mesh access points (APs), including communicating with an uplink AP via the uplink wireless interface and communicating with a downlink AP via the downlink wireless interface. The uplink and downlink wireless interfaces utilize different communication channels having different communication frequencies. The routing unit communicates with one or more local clients via the local wireless interface.

Other features of the present invention will be apparent from the accompanying drawings and from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which like references indicate similar elements.

FIG. 1 is a block diagram illustrating an example of a wireless mesh network configuration which may be used with an embodiment of the invention.

FIG. 2 is a block diagram illustrating inter-mesh AP communications according to one embodiment of the invention.

FIG. 3 is a block diagram illustrating an example of a wireless mesh access point according to one embodiment of the invention.

FIG. 4 is a block diagram illustrating an example of software architecture of a wireless mesh access point according to one embodiment of the invention.

FIG. 5 is a block diagram illustrating a data structure representing a routing table according to one embodiment of the invention.

FIG. 6 is a block diagram illustrating a data structure representing an interface mapping table according to one embodiment of the invention.

FIG. 7 is a block diagram illustrating a data packet used for tunneling according to one embodiment of the invention.

FIG. 8 is a flow diagram illustrating a process for routing a packet in a wireless mesh network according to one embodiment of the invention.

FIG. 9 is a flow diagram illustrating a process for routing a packet in a wireless mesh network according to another embodiment of the invention.

FIG. 10 illustrates a diagrammatic representation of a machine in the exemplary form of a computer system.

DETAILED DESCRIPTION

A dual radio wireless mesh access point is described herein. In the following description, numerous details are set forth to provide a more thorough explanation of embodiments of the present invention. It will be apparent, however, to one skilled in the art, that embodiments of the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring embodiments of the present invention.

Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification do not necessarily all refer to the same embodiment.

According certain embodiments of the invention, multiple wireless path design is provided for both backhaul (e.g., also referred to as a mesh link among multiple mesh APs) and user traffic (e.g., also referred to as a client link between an AP and a local end-user client) to eliminate adjacent AP signal interference degradation. There has been provided a best network throughput vialayer2 fast switching and bridging from AP (access point) to AP to support real time video, voice, and data applications. It is fully compatible with existing access servers, routers, and gateways since existing drivers andlayer3 applications are not modified. It is transparent tolayer3 and up protocols and thus, it is fully compatible with existing network infrastructure or equipments. An AP is directly connected to existing routers, gateways, or AP through, for example, 10/100 Ethernet. The management and security software architecture is configured to support Web based browser and SNMP (simple network management protocol). It also supports WEP (wireless encryption protocol) encryption security across wireless mesh network. Multiple APs can be coupled to each other based on a mesh ID assigned by a user or administrator.

In one embodiment, each node includes multiple wireless interfaces or antennas. For example, a node in a mesh network may include a local AP antenna that operates as an AP for local clients (e.g., end-user clients such as laptop computers, etc.) In addition, the node may further include multiple mesh link AP antennas, one for uplink and one for down link. An uplink interface is configured to communicate with a downlink interface of another node and likewise, a downlink interface of a node is configured to communicate with an uplink interface of another node. Separate channels (e.g., different communication frequencies) are used for uplink and downlink. As result, air link interference can be greatly reduced.

According to another embodiment of the invention, software architecture utilizes existing wireless architecture such as IEEE 802.11 WiFi client and AP drivers, to achieve WIFi mesh network design. As a result, the system can maintain most of the features of WiFi client driver and WiFi access point driver so that it is fully compatible with certain third party products while creating a mesh WiFi network. For example, the software architecture includes an additional layer (also referred to herein as layer2.5) betweenordinary layer2 andlayer3 of a network stack to process data received fromlayer2 driver before delivering the data toordinary layer3 or alternatively, sending the data back down tolayer2 without sending the data tolayer3, dependent upon specific system design. As a result,third party layers2 and3 can be utilized without having to modify a specific driver of a third party vendors.

Further, according to a further embodiment, tunneling is designed to transfer data packets from one node to another node going through standard WiFi client and AP design. For example, each node includes a common AP interface to communicate with multiple clients, where each client communicates with the node via a tunneling technique using the common AP interface. Thus, when a node receive a data packet from a client via normal WiFi client/AP communication protocol, the specific data associated with the sender is encrypted using a variety of data encryption techniques and tunneled within the standard WiFi packets. The receiving node then may decrypt the data packets to reveal who is the actual sender. Further, each node that communicates with the AP interface of a particular node may appear as a virtual node in the particular node.

According to a further embodiment, each node in a WiFi mesh network includes a routing module (also referring to as a bridging module) and a database. The database is used to store information of other nodes which may be collected (e.g., learned) during communications with other nodes including, for example, signal strength, MAC (media access control) addresses, link status, and mesh links (e.g., parent and/or child nodes). The information stored in the database may be used to determine the best route to route the data packets. For example, each node may be assigned with a mesh ID by a user or an administrator. Under certain circumstances, only those nodes having the identical mesh ID may be grouped in a mesh network. Further, the signal strength information may be used to identify the adjacent nodes in the mesh network to determine the shortest route to an AP.

According another embodiment, if a first node has too many hop counts to a master node, and a second node has less hop counts, the first and second nodes may communicate with each other to “relocate” certain routes from the first node to the second node for the load balancing purposes. Note that the above techniques may be implemented in software, hardware, and a combination of both.

FIG. 1 is a block diagram illustrating an example of a wireless mesh network configuration which may be used with an embodiment of the invention. Referring toFIG. 1, wirelessmesh network configuration100 includes, but is not limited to, multiple mesh APs103-106 communicatively coupled to each other as depicted via dash communication links. Some of the APs such as APs103-104 may be coupled via a wired network to agateway device102 which allows traffic from the wireless mesh network to reach an external network or anothernetwork101 such as wide area network (WAN), which may be the Internet.

Each of the APs103-106 includes a local AP link to communicate with local clients (e.g., end-user clients)107-114. Each of the clients107-114 may be associated with any of the APs103-106, which may be statically assigned by an administrator or alternatively, via roaming dynamically. In this example, clients107-108 are associated withAP103; clients109-110 are associated withAP105, clients111-112 are associated withAP106; and clients113-114 are associated withAP104 respectively.

According to one embodiment, each of the APs103-106 includes an uplink interface or antenna and a downlink interface or antenna. An uplink interface of one AP is used to communicate with a downlink interface of another AP. Similarly, a downlink interface of one AP is used to communicate with an uplink interface of another AP. For example, an up link interface ofAP105 may be used to communicate with a downlink interface ofAP103. Likewise, a downlink interface ofAP105 may be used to communicate with an uplink interface ofAP106.

According to one embodiment, communication frequencies for the uplink interface and downlink interface of a particular AP may be different which may be selected or configured by an administrator statically or dynamically (e.g., auto discovery or via frequency hopping). In this way, each backhaul communication link between two APs may have different frequency which greatly reduces the interference.

Furthermore, according to another embodiment, data between two APs may be securely communicated via a tunneling technique. For example, when an AP receives a packet from a local end-user client, the AP may tunnel the packet by encrypting at least the source and destination MAC (media access control) addresses as well as the payload of the packet into a payload of a new packet. The new packet is then package with a new set of source and destination MAC addresses, where the new source MAC address is associated with the AP itself while the destination MAC address is associated with another AP (e.g., next hop). As a result, the new packet can be layer-2 routed to the next AP identified by the new destination MAC address.

When the next hop AP receives the tunneled packet, the next hop AP strips out or removes the source and destination MAC addresses and decrypt the payload of the tunneled packet to reveal the original packet from the end user client. The next hop AP then examines the original destination MAC address to determine whether the destination end-user client is a local end-user client of the next hop AP. If the destination end-user client is a local end-user client, the original packet is transmitted to the identified local end-user client. If the destination end-user client is not a local end-user client, the AP then repackages or re-tunnels the original packet and sends the tunneled packet to another next hop AP, and so on.

FIG. 2 is a block diagram illustrating inter-mesh AP communications according to one embodiment of the invention. For example, APs201-202 may be implemented as any of APs103-106 ofFIG. 1. Referring toFIG. 2,AP201 includes anuplink interface203 and adownlink interface204, as well as alocal link interface205 forlocal clients211. Similarly,AP202 includes anuplink interface207, adownlink interface206, and alocal link interface208 forlocal clients212.Downlink interface204 ofAP201 is used to communicate with an uplink interface of anext hop209.Uplink interface207 ofAP202 is used to communicate with a downlink interface of anext hop210.Uplink interface203 is used to communicate with adownlink interface206 ofAP202.

Typically, a local link interface communicates with a local client using a communication frequency of approximately 2.4 GHz using a standard wireless protocol such as, for example, IEEE 802.11b/g protocol. The communication frequency of the backhaul or mesh link communications is ranging approximately from 4.9 to 5.8 GHz using a standard wireless protocol such as, for example, IEEE 802.11a protocol. However, according to one embodiment, each mesh link may operate at a different communication frequency. For example, with respect to a particular AP, the communication frequency of a downlink interface is different than the communication frequency of an uplink interface. As a result, air interference is greatly reduced.

Furthermore, the communications betweendownlink interface206 ofAP202 anduplink interface203 ofAP201 are securely performed using a tunneling protocol and/or a variety of encryption techniques. For example, whenAP201 receives a packet form alocal client211, theAP201 encrypts almost the entire packet to generate a new packet having a source MAC address ofAP201 and a destination MAC address ofAP202. The new packet is then routed fromAP201 toAP202 viauplink interface203 ofAP201 anddownlink interface206 ofAP202.

WhenAP202 receives the new packet,AP202 strips out the header (e.g., source and destination MAC addresses) and decrypts the payload of the new packet to reveal the original packet originated fromend user client211. Based on the destination MAC address of the revealed original packet,AP202 determines whether the original packet is destined to a local end-user client such asclient212. If the original packet is destined to a local end-user client,AP202 then routes the original packet to the local client vialocal link interface208. However, if the original packet is not destined to a local end-user client,AP202 may repackage or re-tunnel the original packet with a source MAC address ofAP202 and a destination MAC address of a next hop, which may be an AP communicatively coupled viauplink interface207 or another AP communicatively coupled viadownlink interface206.

FIG. 3 is a block diagram illustrating an example of a wireless mesh access point according to one embodiment of the invention. For example,AP300 may be implemented as part ofAP201 orAP202 ofFIG. 2. Referring toFIG. 3, in one embodiment,AP300 includes, but is not limited to multiple wireless interface devices301-304, also referred to herein as RF (radio frequency) or radio cards or devices, each having a corresponding wireless controller and necessary RF circuit, communicatively coupled to each other via bus orinterconnect307. The radio cards301-304 may be provided by a third party vendor which also provides a software driver (e.g.,layer2 to layer7 network driver). In this example,AP300 includes anuplink interface card301 that can be used to communicate with a downlink interface of another AP.AP300 further includes adownlink interface card302 that can be used to communicate with an uplink interface of another AP and a locallink interface card303 used to communicate with a local client. Furthermore, optionally,AP300 includes amonitoring interface card304 used to monitor or survey the mesh networks which may be used to reassign or balance the APs in the network such that the devices in the network can optimally operate.

AP300 further includes one ormore processors305 coupled to thebus307. In addition,AP300 further includes amanagement interface308 to allow amanagement station309 to communicate withAP300 over anetwork310 for management purposes. The routing software (not shown) may be loaded withinmemory306 and executed byprocessor305. For example, each of the interface cards301-304 may be configured by themanagement station309 overnetwork310 to operate in a particular but different frequency to reduce air interference, etc. Each interface card may be assigned with a unique interface identifier (I/F ID) that uniquely identifies the corresponding interface, physically or logically (e.g., virtual). Other configurations may exist.

FIG. 4 is a block diagram illustrating an example of software architecture of a wireless mesh access point according to one embodiment of the invention. For example,software stack400 may be running withinmemory306 byprocessor305 ofFIG. 3. Referring toFIG. 4,software stack400 includes, but is not limited to,layer3 and upnetwork stack402 andlayer2404 that can process data exchanged with hardware such asradio cards405.Radio cards405 may be implemented as any of the radio cards301-304 as shown inFIG. 3. Note thatlayer404 andlayer402 may be provided with thehardware405 from a third party vendor.

In addition, according to one embodiment,software stack400 further includeslayer403, also referred to as layer2.5 logically representing an additional layer betweenlayer2 andlayer3 of OSI (open system interconnection).Layer403 includes arouting logic406 for routing data received from different radio cards vialayer404. Any data for management application such as SNMP (simple network management protocol)application401 is routed vialayer402. In this embodiment, sincelayer403 is inserted betweenlayer404 and402, theordinary layer2 andlayer3 do not need to modify aslayer403 is completely transparent tolayers404 and402.

The data is routed among multiple interfaces (e.g., uplink, downlink, or local link) based on information obtained from routing table408 and/or interface mapping table407. Interface mapping table407 may be implemented in a manner similar to one as shown inFIG. 5. Likewise, routing table408 may be implemented similar to one shown inFIG. 6.

Referring toFIG. 5, interface mapping table500 includes multiple entries. Each entry includes aninterface ID field501, a sourceMAC address field502, and a destinationMAC address field503. Theinterface ID field501 is used to store an ID of a particular interface of the AP. The sourceMAC address field502 is used to store a MAC address corresponding to an interface card (e.g., either uplink or downlink) identified by the interface ID stored in theinterface ID field501. The destinationMAC address field503 is used to store a MAC address of an interface card (e.g., either uplink or downlink) of a next hop AP device. The interface mapping table is used by the routing logic to tunnel a packet to a next hop.

Referring toFIG. 6, a routing table600 includes multiple entries. Each entry includes aMAC address field601 to store a particular MAC address (e.g., source or destination MAC address) and aninterface ID field602 to store an interface ID corresponding to a MAC address stored inMAC address field601. This table is used to determine which interface card that a particular packet should be sent.

FIG. 7 is a block diagram illustrating a data packet used for tunneling according to one embodiment of the invention. Referring toFIG. 7, in this example,packet701 is originally initiated from an end-user client such asclient211 ofFIG. 2. In this example, like a standard TCP/IP packet,packet701 includes, among others, asource MAC address703, a destination MAC address, other layer-3 and upheader705, andpayload706.

Referring toFIGS. 2 and 7, whenAP201 receivespacket701 where AP is configured to maintain its own copy of interface mapping table (e.g., table500 ofFIG. 5) and a routing table (e.g., table600 ofFIG. 6),AP201 may perform a lookup operation at the routing table to determine whether a source MAC address703 (e.g., MAC address representing the end-user client211) exists in the routing table. If not,AP201 may store or insert a new entry into the routing table having thesource MAC address703 and an interface ID corresponding to an incoming interface ofAP201, in this example,interface205.

In addition, according to one embodiment,AP201 may further perform another lookup operation at the routing table based on thedestination MAC address704. It is assumed that an administrator initially has configured all the necessary routing paths in the mesh network. Thus, there should be an entry in the routing table having a MAC address corresponding todestination MAC address704 associated with a particular interface (e.g., outgoing or egress interface) in the routing table. From the routing table, based on thedestination MAC address704, an outgoing interface ID is obtained that corresponds to, in this example,interface203.

Further, according to one embodiment,AP201 may further perform another lookup operation at the interface mapping table based on the interface ID obtained from the routing table to determine a pair ofsource MAC address708 anddestination MAC address709, where thesource MAC address708 represents a MAC address associated with the outgoing interface of current AP and thedestination MAC address709 represents an ingress interface of a next hop AP. As a result, anew packet702 is generated havingsource MAC address708 anddestination MAC address709, where most of theoriginal packet701 having fields703-706 is encrypted (e.g., tunneled) using a variety of encryption methods to generate anew payload707 ofpocket702.Packet702 is then transmitted to anext hop AP202 viainterface203.

WhenAP202 receivespacket702,AP202 strips off the header having at leastsource MAC address708 anddestination MAC address709 and decryptspayload707 to reveal theoriginal packet701. Again, similar to operations performed byAP201,AP202 determines whether the revealedpacket701 is intended for its local end-user client such asclient212. If so, the revealedpacket701 is then transmitted to the local client. Otherwise, thepacket701 is then repackaged and tunneled to another AP using techniques similar to those set forth above. As a result, communications between two AP local networks can be securely performed.

Note that packets701-702 are shown for purposes of illustration only. Other formats may also be applied. For example, instead of wrapping the original MAC addresses of thepacket701 using the AP MAC addresses to generatepacket702, the original MAC addresses ofpacket701 may be replaced by the AP MAC addresses. The original MAC addresses may be relocated to some other locations such as the end ofpacket702.

FIG. 8 is a flow diagram illustrating a process for routing a packet in a wireless mesh network according to one embodiment of the invention. Note thatprocess800 may be performed by processing logic which may include hardware, software, or a combination of both. For example,process800 may be performed by a wireless mesh AP such asAP300 ofFIG. 3. Referring toFIG. 8, atblock801, a first packet (e.g.,packet701 ofFIG. 7) is received via an incoming or ingress interface (e.g., local link interface) from a local end-user client having a source MAC address representing the local end-user client and a destination MAC address representing a destination end-user client.

Atblock802, an outgoing or egress interface (e.g., interface ID) is determined based on the destination MAC address of the first packet. For example, the egress interface ID may be determined via a lookup operation of a routing table maintained within the respective AP (e.g., routing table600 ofFIG. 6). Atblock803, if the source MAC address of the first packet does not exist in the routing table, a new entry is created in the routing table for storing the source MAC address and an interface ID corresponding to an interface from which the first packet is received.

Atblock804, based on the egress interface ID determined above, an AP source MAC address and an AP destination MAC address are determined. For example, the AP source and destination MAC addresses may be determined via a lookup operation on the interface mapping table maintained within the respective AP (e.g., table500 ofFIG. 5). Atblock805, a new packet or a second packet (e.g.,packet702 ofFIG. 7) is created using the AP source and destination MAC address by tunneling the first packet, including encrypting at least the source and destination MAC addresses as well as the payload of the first packet. Thereafter, atblock806 the new packet is transmitted to a proper interface identified by the interface ID, which is then routed to a next hop AP.

FIG. 9 is a flow diagram illustrating a process for routing a packet in a wireless mesh network according to another embodiment of the invention. Note thatprocess900 may be performed by processing logic which may include hardware, software, or a combination of both. For example,process900 may be performed by a wireless mesh AP such asAP300 ofFIG. 3. Referring toFIG. 9, at block901, a first packet is received via an incoming or ingress interface from a previous hop AP, the first packet having a first source MAC address and a first destination MAC address, as well as a payload. The first source MAC address is associated with an egress interface of the previous hop AP and the destination MAC address is associated with an ingress interface of the current hop AP. Note that the ingress interface of the current hop AP may be an uplink interface or a downlink interface. Similarly, an egress interface of a previous hop AP may be an uplink interface or a downlink interface.

Atblock902, the source and destination MAC addresses of the first packet is stripped off and the payload is decrypted to reveal a second packet that has been tunneled within the first packet. The second packet includes a second source MAC address associated with a first end-user client (e.g., original end-user client that initiates the first packet form a local link) and a destination MAC address associated with a second end-user client as a destination end-user client intended to receive the first packet.

Atblock903, it is determined whether the second packet is intended to a local end-user client of a current hop AP (e.g., whether the second end-user client is a local end-user client). For example, a lookup operation may be performed at a routing table maintained by the current hop AP based on the destination MAC address of the second packet (e.g., whether an interface ID corresponding to the destination MAC address of the second packet represents a local link interface of a current hop AP). If the second packet is intended to a local end-user client of a current hop AP, at block904, the second packet is transmitted to the intended local end-user client via a local link interface of the current hop AP.

If the second packet is not intended to a local end-user client of a current hop AP, atblock905, the second packet is then tunneled within a third packet, and the third packet is then transmitted to a next hop AP using techniques similar to those set forth above. Other operations may also be performed.

FIG. 10 illustrates a diagrammatic representation of a machine in the exemplary form of a computer system within which a set of instructions, for causing the machine to perform any one or more of the methodologies discussed herein, may be executed. In alternative embodiments, the machine may be connected (e.g., networked) to other machines in a Local Area Network (LAN), an intranet, an extranet, or the Internet. The machine may operate in the capacity of a server or a client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), a tablet PC, a set-top box (STB), a Personal Digital Assistant (PDA), a cellular telephone, a web appliance, a server, a network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term “machine” shall also be taken to include any collection of machines (e.g., computers) that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein.

Thesystem1000 may be used as a client, a server, a gateway device, or a wireless mesh access point described above. For example,system1000 may be implemented as part of any ofgateway102, clients107-114, or APs103-106 ofFIG. 1 or alternatively,management system309 ofFIG. 3.

As shown inFIG. 10, thesystem1000, which is a form of a data processing system, includes a bus orinterconnect1002 which is coupled to one ormore microprocessors1003 and aROM1007, avolatile RAM1005, and anon-volatile memory1006. Themicroprocessor1003 is coupled tocache memory1004 as shown in the example ofFIG. 10.Processor1003 may be, for example, a PowerPC microprocessor or an Intel compatible processor. Alternatively,processor1003 may be a digital signal processor or processing unit of any type of architecture, such as an ASIC (Application-Specific Integrated Circuit), a CISC (Complex Instruction Set Computing), RISC (Reduced Instruction Set Computing), VLIW (Very Long Instruction Word), or hybrid architecture, although any appropriate processor may be used.

Thebus1002 interconnects these various components together and also interconnects thesecomponents1003,1007,1005, and1006 to a display controller anddisplay device1008, as well as to input/output (I/O)devices1010, which may be mice, keyboards, modems, network interfaces, printers, and other devices which are well-known in the art.

Typically, the input/output devices1010 are coupled to the system through input/output controllers1009. Thevolatile RAM1005 is typically implemented as dynamic RAM (DRAM) which requires power continuously in order to refresh or maintain the data in the memory. Thenon-volatile memory1006 is typically a magnetic hard drive, a magnetic optical drive, an optical drive, or a DVD RAM or other type of memory system which maintains data even after power is removed from the system. Typically, the non-volatile memory will also be a random access memory, although this is not required.

WhileFIG. 10 shows that the non-volatile memory is a local device coupled directly to the rest of the components in the data processing system, embodiments of the present invention may utilize a non-volatile memory which is remote from the system; such as, a network storage device which is coupled to the data processing system through a network interface such as a modem or Ethernet interface. Thebus1002 may include one or more buses connected to each other through various bridges, controllers, and/or adapters, as is well-known in the art. In one embodiment, the I/O controller1009 includes a USB (Universal Serial Bus) adapter for controlling USB peripherals. Alternatively, I/O controller1009 may include an IEEE-1394 adapter, also known as FireWire adapter, for controlling FireWire devices.

Thus, a dual radio wireless mesh access point has been described herein. Some portions of the preceding detailed descriptions have been presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the ways used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of operations leading to a desired result. The operations are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the above discussion, it is appreciated that throughout the description, discussions utilizing terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

Embodiments of the present invention also relate to an apparatus for performing the operations herein. This apparatus may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), erasable programmable ROMs (EPROMs), electrically erasable programmable ROMs (EEPROMs), magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.

The algorithms and displays presented herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the required method operations. The required structure for a variety of these systems will appear from the description below. In addition, embodiments of the present invention are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of embodiments of the invention as described herein.

A machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, a machine-readable medium includes read only memory (“ROM”); random access memory (“RAM”); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.); etc.

In the foregoing specification, embodiments of the invention have been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications may be made thereto without departing from the broader spirit and scope of the invention as set forth in the following claims. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

Claims (16)

1. A wireless mesh access point (AP), comprising:

an uplink interface;

a downlink interface;

a local link interface;

a routing unit coupled to the uplink, downlink, and local link interfaces, wherein the routing unit is configured to route data packets to other wireless mesh access points (APs), including communicating with an uplink AP via the uplink interface and communicating with a downlink AP via the downlink interface, wherein the uplink and downlink wireless interfaces utilize different communication channels having different communication frequencies, wherein the routing unit is configured to communicate with one or more local clients via the local link interface; and

a memory coupled to the routing unit for storing a routing table and an interface mapping table, wherein the routing table includes a first plurality of entries, each having a MAC address and an interface ID identifying an interface associated with the MAC address of the respective entry, and wherein the interface mapping table includes a second plurality of entries, each having an interface ID identifying an interface, a source MAC address, and a destination MAC address, the source and destination MAC addresses being associated with the interface ID of the respective entry,

wherein in response to a first packet received from a local client via the local link interface, the routing unit is configured to determine, via the routing table, an egress interface based on a destination media access control (MAC) address of the first packet, the egress interface being one of the uplink interface and the downlink interface,

wherein based on the egress interface determined using the routing table, the routing unit is configured to determine, using the interface mapping table, a source MAC address associated with the egress interface and a destination MAC address associated with a next hop wireless mesh AP, and

wherein the routing unit is configured to generate a second packet by encrypting the first packet therein, using the source MAC address and the destination MAC address obtained via the interface mapping table as source and destination MAC addresses of the second packet, and to transmit the second packet via the determined egress interface to the next hop wireless mesh AP in the wireless mesh network, the first packet being encrypted within a payload of the second packet.

2. The wireless mesh AP ofclaim 1, wherein the uplink interface comprises a first antenna, wherein the downlink interface comprises a second antenna, wherein the local link interface comprises a third antenna, and wherein the wireless mesh AP further comprises a monitoring interface having a fourth antenna used to monitor traffic of the wireless mesh network for balancing a plurality of wireless mesh APs in the wireless mesh network, such that devices in the wireless mesh network can operate in an optimal manner.

3. The wireless mesh AP ofclaim 1, wherein the routing unit further determines whether tile routing table includes an entity having a MAC address that matches a source MAC address of the first packet, and wherein if there is no entry in the routing table that matches the source MAC address of the first packet, a new entry is created within the routing table having the source MAC address of the first packet and an interface ID identifying the local link interface.

4. A wireless mesh network, comprising:

a plurality of wireless mesh access points (APs) communicatively coupled to each other via a plurality of mesh links, wherein each wireless mesh AP includes

an uplink interface,

a downlink interface,

a local link interface,

a routing unit coupled to the uplink, downlink, and local link interfaces, wherein the routing unit is configured to route data packets to other wireless mesh access points (APs), including communicating with an uplink AP via the uplink interface and communicating with a downlink AP via the downlink interface, wherein the uplink and downlink wireless interfaces utilize different communication channels having different communication frequencies, wherein the routing unit is configured to communicate with one or more local clients via the local link interface, and

a memory coupled to the routing unit for storing a routing table and an interface mapping table, wherein the routing table includes a first plurality of entries, each having a MAC address and an interface ID identifying an interface associated with the MAC address of the respective entry, and wherein the interface mapping table includes a second plurality of entries, each having an interface ID identifying an interface, a source MAC address, and a destination MAC address, the source and destination MAC addresses being associated with the interface ID of the respective entry,

wherein in response to a first packet received from a local client via tile local link interface, the routing unit is configured to determine, via the routing table, an egress interface based on a destination media access control (MAC) address of the first packet, the egress interface being one of the uplink interface and the downlink interface,

wherein based on the egress interface determined using the routing table, the routing unit is configured to determine, using the interface mapping table, a source MAC address associated with the egress interface and a destination MAC address associated with a next hop wireless mesh AP, and

wherein the routing unit is configured to generate a second packet by encrypting the first packet therein, using the source MAC address and the destination MAC address obtained via the interface mapping table as source and destination MAC addresses of the second packet, and to transmit the second packet via the determined egress interface to the next hop wireless mesh AP in the wireless mesh network, the first packet being encrypted within a payload of the second packet.

5. The wireless mesh network ofclaim 4, wherein the uplink interface comprises a first antenna, wherein the downlink interface comprises a second antenna, wherein the local link interface comprises a third antenna, and wherein the wireless mesh AP further comprises a monitoring interface having a fourth antenna used to monitor traffic of the wireless mesh network for balancing a plurality of wireless mesh APs in the wireless mesh network, such that devices in the wireless mesh network can operate in an optimal manner.

6. The wireless mesh network ofclaim 4, wherein the routing unit further determines whether the routing table includes an entry having a MAC address that matches a source MAC address of the first packet, and wherein if there is no entry, in the routing table that matches the source MAC address of the first packet, a new entry is created within the routing table having the source MAC address of the first packet and an interface identifying the local link interface.

7. The wireless mesh AP ofclaim 3, wherein in response to a third packet received from a second wireless mesh AP via an ingress interface, the ingress interface being one of the uplink interface and the downlink interface, the routing unit is configured to decrypt a payload of the third packet to reveal a fourth packet encrypted therein, wherein the routing unit is configured to determine a second egress interface, using the routing table, based on a destination MAC address of the fourth packet, the second egress interface being one of the uplink interface, downlink interface, and the local link interface, and wherein the routing unit is configured to transmit the fourth packet via the second egress interface.

8. The wireless mesh AP ofclaim 7, wherein if the second egress interface corresponds to the local link interface, the routing unit is configured to route the fourth packet to a second local client via the local link interface.

9. The wireless mesh AP ofclaim 8, wherein if the second egress interface is not the local link interface, the routing unit is configured to determine, using the interface mapping table, a second source MAC address and a second destination MAC address based on the second egress interface, the second source MAC address being associated with the second egress interface and the second destination MAC address being associated with the second next hop wireless mesh AP, and wherein the routing unit is configured to route the fourth packet to a second next hop wireless mesh AP, using the second source and destination MAC addresses via the second egress interface.

10. The wireless mesh AP ofclaim 9, wherein the routing unit is configured to generate a fifth packet having the second source MAC address and the second destination MAC address as a source MAC address and a destination MAC address of the fifth packet respectively, wherein the fourth packet is encrypted within a payload of the fifth packet, and wherein the fifth packet is transmitted to the second next hop wireless mesh AP via the second egress interface using the second source and destination MAC addresses.

11. The wireless mesh AP ofclaim 10, wherein the routing unit comprises a routing logic operating logically as a network layer2.5 between layer2 and layer3 of a standard network stack without having to modify the layer2 and the layer3 of the standard network stack, and wherein the network layer2.5 is configured to intercept traffic between the layer2 and the layer3 of the standard network stack.

12. The wireless mesh network ofclaim 6, wherein in response to a third packet received from a second wireless mesh AP via an ingress interface, the ingress interface being one of the uplink interface and the downlink interface, the routing unit is configured to decrypt a payload of the third packet to reveal a fourth packet encrypted therein, wherein the routing unit is configured to determine a second egress interface, using the routing table, based on a destination MAC address of the fourth packet, the second egress interface being one of the uplink interface, downlink interface, and the local link interface, and wherein the routing unit is configured to transmit the fourth packet via the second egress interface.

13. The wireless mesh network ofclaim 12, wherein if the second egress interface corresponds to the local link interface, the routing unit is configured to route the fourth packet to a second local client via the local link interface.

14. The wireless mesh network ofclaim 13, wherein if the second egress interface is not the local link interface, the routing unit is configured to determine, using the interface mapping table, a second source MAC address and a second destination MAC address based on the second egress interface, the second source MAC address being associated with the second egress interface and the second destination MAC address being associated with the second next hop wireless mesh AP, and wherein the routing unit is configured to route the fourth packet to a second next hop wireless mesh AP, using the second source and destination MAC addresses via the second egress interface.

15. A method performed by a wireless mesh access point (AP), comprising:

receiving, by a routing unit of the wireless mesh AP, a first packet from a local client, the wireless mesh AP having an uplink interface, a downlink interface, and a local link interface, the first packet being received from the local client via the local interface, wherein the routing unit is configured to route data packets to other wireless mesh access points (APs), including communicating with an uplink AP via the uplink interface and communicating with a downlink AP via the downlink interface, wherein the uplink and downlink wireless interfaces utilize different communication channels having different communication frequencies, wherein the routing unit is configured to communicate with one or more local clients via the local link interface;

determining, by the routing unit, via a routing table maintained within a memory coupled to the routing unit, an egress interface based on a destination media access control (MAC) address of the first packet, the egress interface being one of the uplink interface and the downlink interface;

based on the egress interface determined using the routing table, determining, by the routing unit, using an interface mapping table maintained within the memory, a source MAC address associated with the egress interface and a destination MAC address associated with a next hop wireless mesh AP;

generating, by the routing unit, a second packet by encrypting the first packet within a payload of the second packet, using the source MAC address and the destination MAC address obtained via the interface mapping table as source and destination MAC addresses of the second packet; and

transmitting, by the routing unit, the second packet via the determined egress interface to the next hop wireless mesh AP in the wireless mesh network,

wherein the routing table includes a first plurality of entries, each having a MAC address and an interface ID identifying an interface associated with the MAC address of the respective entry, and wherein the interface mapping table includes a second plurality of entries, each having an interface ID identifying an interface, a source MAC address, and a destination MAC address, the source and destination MAC addresses being associated with the interface ID of the respective entry.

16. The method ofclaim 15, wherein the uplink interface comprises a first antenna, wherein the downlink interface comprises a second antenna, wherein the local link interface comprises a third antenna, and wherein the wireless mesh AP further comprises a monitoring interface having a fourth antenna used to monitor traffic of the wireless mesh network for balancing a plurality of wireless mesh APs in the wireless mesh network, such that devices in the wireless mesh network can operate in an optimal manner.

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